This invention relates to sealed electrical devices, such as relays for automobiles mounted under the hoods thereof, used in environments where rain spray can gain access to the mounting locations of the devices. In such cases, it is important to the reliability of the devices that water does not gain access to them.
There is disclosed in recently granted U.S. Pat. No. 4,320,369 a unique plug-in relay construction useable in automobiles and which includes a support base of insulating material formed by a pair of insulating plates held together by rivets and between which are clamped the laterally extending portions of terminal blade members. A relay is supported on the innermost of these plates. A housing is disclosed which encloses the relay, the housing being an inverted cup-shaped member with the bottom edges of the housing resting upon a peripheral shoulder on the support base. In such a construction, splashing rainwater can gain ready access to the interior of the housing and the peripheral shoulder on the support base. This relay design is adapted primarily to an application where each relay assembly plugs into a stationary socket base mounted in a horizontal wall.
In many different relay unit designs, the relay unit housing is mounted by a bracket on a wall of the automobile involved. A cable with a connector block is applied to the terminal blade members of the relay. The connector block is commonly provided with a releasable resilient latching arm which interlocks with connector block guide wall extending from the relay support base. If such a connector block were to be used with the two-part riveted support base construction disclosed in said patent, if the user forgetfully tries to pull the connector block from the relay blade terminal members without releasing the connector latching arm from the support base connector guide wall, the forces involved can sometimes break the plastic rivets which connect the insulating plates forming the support base for the relay.
When relay assemblies are made with mounting brackets, the brackets have generally been formed integrally with the housings thereof so that a different housing design is often necessary for relay assemblies to be used in automobiles of varying designs where the points of connection of the brackets to the mounting walls involved vary with the different models of the automobiles involved.
The various aspects of the present invention to be described provides a plug-in electrical device, like a relay, which is an improvement over prior plug-in electrical device construction known to us in that the electrical device of the invention avoids one or more, and preferably all of, the prior art disadvantages described above.